In general, radar tri-lateralization position locators are utilized in navigation and the like to determine the position of ships relative to two or more fixed shore stations. The baseline or distance between the two stations must always be included in the position calculations. In these types of prior art devices the shore stations are never moved and, may include, a relatively large number of stations positioned along a shore or navigation course so that a ship may use signals from different stations along its course to determine its position. Only two stations are used in each calculation and, since the stations are permanently positioned at known locations, the distance between these stations is always known and can be readily included into the computations.
When a radar electronic positioning system is utilized for guiding airplanes, for example, in crop dusting, spraying forests, or in any other applications where a uniform flight pattern is required, reference stations must be set up for each operation and the distance between the reference stations (the baseline) is not always readily available. For example, if a large area of forest is to be sprayed, it may be necessary to set the reference stations on the peaks of two hills. In this instance it may be very difficult to determine the distance between the two reference stations. Further, because two reference stations are used the distance between these stations must be included in the computations for proper tri-lateralization. All of the known prior art requires an accurate knowledge of the distance between the reference stations and the introduction of this distance into the computations prior to the operation. Further, all of the known prior art systems utilize extremely complex apparatus which is very costly and requires much of the pilots time for setting up the operation and operating during the spraying or the actual flight.